public function __construct(Settings $settings)
{
$storage = new FileStorage($settings->temp_dir);
$this->settings = $settings;
parent::__construct($storage);
$this->cache_data = $this->load($this->settings->cache_name);
if ($this->cache_data === null) {
$this->save($this->settings->cache_name, array());
$this->cache_data = array();
}
}